吸附诱导的分子内部二极管:相关的分子构造和接口电子结构
Norbert Koch1, Alexander Gerlach, Steffen Duhm
1Humboldt-Universität zu Berlin, Institut für Physik, Newtonstrasse 15, 12489 Berlin, Germany. norbert.koch@physik.hu-berlin.de
Journal of the American Chemical Society
|May 16, 2008
概括
在铜上研究五烯 (PEN) 和 perfluoropentacene (PFP) 发现了不同的分子结构. 这种结构差异解释了尽管有不同的电离能,但类似的孔注射屏障,挑战了简单的调整假设.
科学领域:
- 表面科学是一门学科.
- 有机电子 有机电子
- 材料化学 材料化学
背景情况:
- 了解有机分子-金属接口对于有机电子设备至关重要.
- 五烯 (PEN) 和 perfluoropentacene (PFP) 是具有不同电子特性的关键有机半导体.
- 分子结构,电离能和电荷注入障碍在接口之间的关系需要详细的研究.
研究的目的:
- 研究 (Cu) 上的五 (PEN) 和完全 (PFP) 的界面结构和电子特性.
- 阐明在这些有机金属接口处控制孔注入屏障的因素.
- 评估调电离能用于控制电荷注入屏障的适用性.
主要方法:
- 使用光电子光谱,X射线静电波 (XSW) 和扫描道显微镜.
- 进行理论建模以补充实验观测.
- 分析了碳结合距离,分子构造和分子内部二极体.
主要成果:
- 在Cu上观察到PEN (2.34 Å) 和PFP (2.98 Å) 的平均碳结合距离显著不同.
- XSW数据显示了PFP的吸附诱导的非平面形状,产生了分子内部二极管 (约. 0.5 D) 的时间.
- 尽管有不同的电离能 (PEN:5.00 eV,PFP:5.85 eV),但可比的孔注入障碍被测量出来 (PEN:1.10 eV,PFP:1.35 eV).
结论:
- PFP的非平面形状和诱导二极体显著影响其界面行为.
- 类似的孔注射障碍产生的因素的复杂相互作用,不仅仅是分子电离能.
- 通过调整有机/金属接口上的分子电离能来轻松调整电荷注入屏障的假设并不普遍适用.
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